New Processing Facility Would Have Access to NGL Fractionation, NGL
Connections to Shell's Proposed Petrochemical Facility, and the
Bluegrass Pipeline JV

Williams Partners L.P. (NYSE:WPZ) announced today that it has agreed to
launch a new midstream joint venture with Shell to provide gas gathering
and gas processing services for production located in Northwest
Pennsylvania. The venture will invest in both wet-gas handling
infrastructure and dry gas infrastructure serving Marcellus and Utica
Shale wells in the area.

The new venture, Three Rivers Midstream, has signed a long-term
fee-based dedicated gathering and processing agreement for Shell's
production in the area, including approximately 275,000 dedicated acres.
The joint venture also plans to pursue gathering and processing
agreements with other producers in the liquids-rich areas of Northeast
Ohio in addition to Northwest Pennsylvania.

Three Rivers plans to construct a 200 million cubic feet per day
(MMcf/d) cryogenic gas processing plant and related facilities. The
location will be determined at a later date. The planned large-scale gas
processing complex would be expandable as Three Rivers' business grows.
The initial plant is expected to be placed into service by second
quarter 2015.

"This new joint venture builds on our strategy of creating large-scale
infrastructure solutions that will provide Shell and other producers
with access to the best markets for their natural gas and natural gas
liquids, whether they be in the Northeast or the Gulf Coast," said Alan
Armstrong, chief executive officer of Williams Partners' general partner.

"The system is expected to be connected to two major proposed
developments in Pennsylvania – Shell's proposed ethylene cracker
(feasibility still being studied) in Beaver County and the proposed
Williams - Boardwalk joint venture to develop the Bluegrass Pipeline
system that would deliver Marcellus and Utica liquids to the rapidly
expanding Gulf Coast and export markets. The proposed Bluegrass pipeline
is targeting a late 2015 in-service date.

"Similar to our strategy of creating a significant supply hub in the dry
gas area of northeast Pennsylvania, Three Rivers will create a major
supply hub in northwest Pennsylvania, but with the added benefit of
large-scale NGL pipeline infrastructure and expanded market options to
support wet-gas production in this area," Armstrong said.

Joint Venture Ownership, Initial Capital Spending

Williams Partners will initially own substantially all of Three Rivers
Midstream and operate the assets. Shell has the right to invest capital
and increase its ownership prior to mid-2015.

Williams Partners' portion of initial capital expenditures on the Three
Rivers plant, not including the gathering system, is expected to be
approximately $150 million. Subsequent capital investment is expected as
the joint venture's business and scale increases.

About Williams Partners L.P. (NYSE: WPZ)

Williams Partners L.P. is a leading diversified master limited
partnership focused on natural gas transportation; gathering, treating,
and processing; storage; natural gas liquid (NGL) fractionation; and oil
transportation. The partnership owns interests in three major interstate
natural gas pipelines that, combined, deliver 14 percent of the natural
gas consumed in the United States. The partnership's gathering and
processing assets include large-scale operations in the U.S. Rocky
Mountains, both onshore and offshore along the Gulf of Mexico and a
growing presence in the Marcellus and Utica shales. Williams (NYSE: WMB)
owns approximately 68 percent of Williams Partners, including the
general-partner interest. More information is available at www.williamslp.com,
where the partnership routinely posts important information.

Portions of this document may constitute "forward-looking statements"
as defined by federal law. Although the partnership believes any such
statements are based on reasonable assumptions, there is no assurance
that actual outcomes will not be materially different. Any such
statements are made in reliance on the "safe harbor" protections
provided under the Private Securities Reform Act of 1995. Additional
information about issues that could lead to material changes in
performance is contained in the partnership's annual reports filed with
the Securities and Exchange Commission.